STABILITY AND VIRUS-INHIBITORY EFFECTS OF RECOMBINANT RECEPTOROTOXINSBASED ON HUMAN T-LYMPHOCYTE CD4 RECEPTOR AND DIPHTHERIA-TOXIN

The causes of differences in the stability of CD4 receptor and diphthe rial toxin based recombinant receptorotoxins synthesized in E.coli and differing by their primary structure were under study. Insertion of a CD4 receptor fragment, responsible for HIV binding, on the N terminus of hybrid protein was found to lend to a drastic reduction of tile st ability of the hybrid polypeptide in E.coli and to impossibility of ob taining full-size protein product. In vitro experiments on a model of human T lymphocyte culture demonstrated that recombinant receptorotoxi n stably expressed in E.coli inhibited the cytopathic effect of type 1 HIV and the effect of syncytium formation induced by the virus.